Ventilation Device and Insertion System Therefor

ABSTRACT

A ventilation device includes a hollow body having a main portion, at least one distal member coupled to a distal end of the main portion and at least one proximal member coupled to a proximal end of the main portion. The at least one distal member is formed of a shape memory material. The hollow body includes a deployed state for maintaining an opening in an anatomical structure and an undeployed state. The shape memory material forms the at least one distal member into a deployed position. The shape memory material is reversibly deformed from the deployed state into the undeployed state such that at least the distal member changes in shape to an undeployed position, while the main portion of the hollow body remains unchanged.

BACKGROUND

Placement of middle ear ventilation tubes in the tympanic membrane is acommon pediatric surgical procedure for the treatment of middle earinfection or otitis media. Also known as tympanostomy tubes or pressureequalizing (PE) tubes, the procedure involves creating an incision(i.e., a myringotomy) in the tympanic membrane and placing a tube in theincision to allow ventilation, pressure equalization and drainage fromthe middle ear out through the ear canal. The tube can remain in the earfor months or years.

Currently, a tube is placed in the tympanic membrane via visualizationthrough a microscope. A sharp blade is used to create the incision andsurgical instruments are used to manipulate the tube into the incision.In the confined space of the ear canal, placement of the tube can bedifficult and it is not uncommon for the tube to dislodge from thesurgical instrument or for it to accidentally extract from the tympanicmembrane before being fully seated, requiring multiple attempts beforesuccessful placement is achieved.

Because the middle ear is highly innervated, repeated manipulation ofthe tympanic membrane is painful enough that patients, especially youngchildren, who make up the majority of tube recipients, require generalanesthesia, which is costly and poses additional risks. Surgicallyinserting the PE tube can be difficult, especially in aligning theflange at one end of the tube with the incision and in the use ofmultiple different surgical instruments to perform the procedure. Inaddition, the large retention flanges included in most tubes make themdifficult to maneuver in the ear canal and will actually block theclinician's view of the incision site.

The discussion above is merely provided for general backgroundinformation and is not intended to be used as an aid in determining thescope of the claimed subject matter.

SUMMARY

A ventilation device includes a hollow body having a main portion, atleast one distal member coupled to a distal end of the main portion andat least one proximal member coupled to a proximal end of the mainportion. The at least one distal member is formed of a shape memorymaterial. The hollow body includes a deployed state for maintaining anopening in an anatomical structure and an undeployed state. The shapememory material forms the at least one distal member into a deployedposition. The shape memory material is reversibly deformed from thedeployed state into the undeployed state such that at least the distalmember changes in shape to an undeployed position, while the mainportion of the hollow body remains unchanged.

The main portion includes inner and outer walls extending from thedistal end to the proximal end. The outer wall of the main portion isdefined by a continuous, fixed outer width. The at least one distalmember extends from the distal end of the main portion to an outer endthat is located within the defined outer width of the main portion in anundeployed state and the outer end of the at least one distal member islocated outwardly from the defined outer width of the main portion in adeployed state. The at least one proximal member extends from theproximal end of the main portion to an outer end that is locatedoutwardly from the defined outer width of the main portion in both anundeployed state and in a deployed state.

An insertion device for inserting the ventilation device is alsoprovided. A hollow sheath member includes a distal end having a cuttingedge and a proximal end. The hollow sheath member is configured to atleast partially surround the ventilation device. A rod member includes adistal end. The distal end of the rod member is located within thesheath member and is configured to be adjacent the proximal end of theventilation device. An actuator is configured to hold the distal end ofthe rod member adjacent to the proximal end of the ventilation devicewhile simultaneously retracting the sheath member from around theventilation device and sliding it over the rod member.

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter. The claimed subject matter is not limited to implementationsthat solve any or all disadvantages noted in the background.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a simplified diagrammatic view of an ear.

FIGS. 2A-2C illustrate a ventilation device at least partiallycomprising a shape memory material under one embodiment.

FIG. 3 illustrates a ventilation device at least partially comprising ashape memory material under another embodiment.

FIGS. 4A-4C illustrate a ventilation device at least partiallycomprising a shape memory material under yet another embodiment.

FIGS. 5A-5C illustrate a ventilation device at least partiallycomprising a shape memory material under yet another embodiment.

FIGS. 6A-6D illustrate a ventilation device at least partiallycomprising an elastic deformation material under one embodiment.

FIGS. 7A-7D illustrate yet another embodiment of a ventilation device atleast partially comprising a shape memory material.

FIGS. 8A-8B illustrate yet another embodiment of a ventilation device atleast partially comprising an elastic deformation material.

FIGS. 9A-9B illustrate a ventilation device at least partiallycomprising a material that mechanically deforms in-situ when insertedinto a tympanic membrane under one embodiment.

FIGS. 10A-10B illustrate ventilation devices that when unconstrained canexpand when inserted into a tympanic membrane under one embodiment.

FIGS. 11A-11E illustrate a ventilation device at least partiallycomprising a shape memory material under yet other embodiments.

FIGS. 12A-12D illustrate different views of an insertion device for usein inserting and deploying the ventilation device of FIGS. 11A-11D underone embodiment.

FIGS. 13A-13D illustrate a process of inserting and deploying theventilation device of FIGS. 11A-11D using the insertion deviceillustrated in FIGS. 12A-12C under one embodiment.

FIG. 14 illustrates an insertion device for use in inserting anddeploying a ventilation device under another embodiment.

FIG. 15 illustrates an insertion device for use in inserting anddeploying a ventilation device under yet another embodiment.

FIGS. 16A-16B illustrate an insertion device for use in inserting anddeploying a ventilation device under yet another embodiment.

FIG. 17 illustrates an insertion device for use in inserting anddeploying a ventilation device under yet another embodiment.

FIGS. 18A-18C illustrate an insertion device for use in inserting anddeploying a ventilation device under yet another embodiment.

FIGS. 19A-19C illustrate an insertion device for use in inserting anddeploying a ventilation device under yet another embodiment.

FIG. 20 illustrates an insertion device for use in inserting anddeploying a ventilation device under yet another embodiment.

DETAILED DESCRIPTION

Embodiments described are directed to various ventilation devices andinsertion systems for inserting ventilation devices in differentmembranes of a body. In one particular embodiment, a ventilation deviceincludes a shape memory material that allows the device to remain in adeformed state during insertion into a body. After insertion through themembrane of interest, it is allowed to re-form its flanges or membersin-situ to anchor it in place. The deformed ventilation device and theinsertion device that places the device in the membrane allows forminimally invasive ventilation system placement, which reduces the pain,cost and risks associated with conventional procedures and devices.

FIG. 1 illustrates a system of organs in an ear 10 of a body thatenables a person to detect sound. Ear 10 is able to change soundpressure waves into a signal of nerve impulses to be processed by thebrain. Ear 10 includes an outer ear 12, a middle ear 14 and an inner ear16. Outer ear 12 collects sound and includes the pinna 18, the ear canal20 and an outer most layer of the ear drum or tympanic membrane 22.Pinna 18 helps direct sound through ear canal 20 to tympanic membrane22. Middle ear 14 includes an air-filled cavity 24 having an opening forthe Eustachian tube 26 that is located behind tympanic membrane 22.Middle ear 14 also includes ossicles bones 28. Inner ear 16 includes thefluid-filled cochlea 30 and the semicircular canals 32. Cochlea 30 isthe auditory portion of the inner ear, while semicircular canals 32 areattuned to both gravity and motion. The ossicles bones 28 transmit soundfrom the air in cavity 24 to cochlea 30. Fluid in cochlea 30 moves inresponse to the vibrations coming from middle ear 14. The motion of thefluid is converted to electrical impulses, which travel along theauditory nerve 34 to structures in the brainstem for further processing.Eustachian tube 26 couples cavity 24 of middle ear 14 to the nose andmouth of a human. In a normal state, Eustachian tube 26 is collapsed.However, Eustachian tube 26 can open and close to equalize pressure incavity 24.

An infection of the middle ear 14 can result in a build up of fluid andincreased pressure in cavity 24 causing severe pain. Children are oftenprone to infections of middle ear 14 because of their underdevelopedEustachian tube 26. A myringotomy is a surgical procedure in which atiny incision is created in tympanic membrane 22 to relieve pressurecaused by the excessive buildup of fluid due to an infection of themiddle ear 14. If a patient requires a myringotomy, this generallysuggests that Eustachian tube 26 is either partially or completelyobstructed and is not able to perform its proper functions

In some cases, besides making an incision in tympanic membrane 22, aventilation device is inserted into the opening. Insertion of aventilation or pressure equalizing (PE) device can allow externalventilation of middle ear 14 for an extended period of time. However, inthe confined space of ear canal 20, especially an ear canal of a child,insertion of a ventilation device can be difficult. In one example, theincision made in tympanic membrane 22 is often made too large relativeto the ventilation device. In such an example, the device will fall outmuch earlier than desired. In another example, many surgical tools needto be used to insert the device, such as a blade, a funnel (to visualizetympanic membrane 22), forceps (to deliver the device), suction and amicroscope. Therefore, much time is needed to prepare for the relativelysimple surgery and additional time is needed during the procedure toswitch between use of the instruments. Although this relatively briefprocedure can be performed on an outpatient basis, in general, childrenrequire a general anesthetic such that they remain co-operative duringthe procedure. Administering anesthetic increases the time of theprocedure as well as cost. A device that can alleviate thesedisadvantages can greatly enhance patient comfort as well as reduceprocedural time and undue injury to tympanic membrane 22, whilesimultaneously simplifying the procedure for physicians.

As discussed above, embodiments described are directed towards devices,systems and procedures for delivering a ventilation structure to amembrane of a body, such as tympanic membrane 22 for treatment of amiddle ear infection or otitis media. It should be realized, though,that embodiments described can be used to deliver and maintain anopening in any anatomical structure of the body whether the opening isnaturally occurring or surgically created. In addition, embodiments arenot limited to just ear ventilation, but could provide communicationbetween any two areas in a body separated by a membrane or barrier.Embodiments described are also directed to the ventilation structureitself.

While embodiments of the ventilation device are illustrated as a hollowbody, the device can also be a ‘plug’ with no internal passageway. Aplug could be used to block openings in a membrane, or create amechanical communication between two spaces separated by a membrane,such as a membrane of a sinus cavity. The device can also be used tocreate communication between two lumens such as formation of vascularshunts or applied to the gastrointestinal tract and biliary system. Thedeployed distal members of the device may also provide betterpositioning of stents, in that, the larger ends can limit movement ofthe device/stent. For example, tracheal, bronchial, and esophagealstents are at high risk of movement from an originally deployedposition. This is likely due to the symmetrical cylinder shape of thestent/device. Also, the device can be a minimally invasive way to deploya trocar device/site.

The device can also be used in tympanometry. For example, a device thatforms an airtight fit around a tympanometry probe could be placed intothe ear canal (instead of through the tympanic membrane). The selfexpanding device would seal off the middle ear, allowing the pressure tobe accurately varied in the proximal ear canal. It is also possible thata device delivery system by itself could be used for tympanometrywithout the need for the device component. Expansion components (such asballoons) on a delivery system could be used to fill and seal off theear canal.

FIGS. 2A-2C illustrate a ventilation device 200 comprised at leastpartially of a shape memory material in accordance with one embodiment.In the perspective view of FIG. 2A, ventilation device 200 is in anundeployed state. In the perspective view of FIG. 2B and in the sideview of FIG. 2C, ventilation device 200 is in a deployed state.Ventilation device 200 includes a hollow body 202 made at leastpartially of a shape memory metal or polymer. Example shape memorymetals include shape memory alloys, such as a nickel-titanium alloycoined Nitinol and various aluminum alloys coined Algiloys (i.e.,copper-zinc-aluminum-nickel and copper-aluminum-nickel). Example shapememory polymers include oligo (ε-caprolactone) diol and crystallisableoligo (ρ-dioxanone) diol. However, it should be realized that othertypes of shape memory alloys and polymers can be used. Althoughventilation device 200 is illustrated as having a cylindrical, tube-likestructure, other geometries are possible.

In one embodiment, ventilation device 200 is formed at least partiallywith a shape memory material in the deployed state as illustrated inFIGS. 2B and 2C. After formation, reversible deformation is applied tothe ventilation device to place it in the undeployed state asillustrated in FIG. 2A. In the undeployed state, ventilation device 200is able to be delivered to the tympanic membrane or other anatomicalstructure for insertion. Upon addition of heat, such as heat appliedfrom a living body, and removal of any mechanical constraint, theventilation device 200 regains its deployed configuration as illustratedin FIGS. 2B and 2C.

In FIGS. 2A-2C, body 202 of ventilation device 200 includes a mainportion 204, a distal member 206 and a proximal member 208. Distalmember 206 is coupled to a distal end 210 of main portion 204, whileproximal member 208 is coupled to a proximal end 212 of main portion204. While the entire body 202 can be formed of a shape memory material,it should be realized that it is possible for main portion 204 or partsof main portion 204 to be formed of a different material than the shapememory materials of distal and proximal members 206 and 208.

Main portion 204 includes an outer wall 203 and an inner wall 205. Outerwall 203 and inner wall 205 extend from distal end 210 to proximal end212. As illustrated in FIG. 2C, outer wall 203 is defined by andincludes a continuous, fixed outer width or outer diameter 207 and innerwall 205 is defined by and includes a continuous, fixed inner width orinner diameter 209. In other words, main portion 204 remain unchangedbetween an undeployed state and a deployed state.

Both distal member 206 and proximal member 208 have outer ends 214 and216 and inner ends 218 and 220. Inner ends 218 and 220 are coupled todistal end 210 and proximal end 212, respectively, of main portion 204.In the undeployed state or reversible deformation state illustrated inFIG. 2A, outer ends 214 and 216 of members 206 and 208 are locatedoutwardly from the defined outer width 207 of main portion 204. In thedeployed state illustrated in FIGS. 2B-2C, distal member 206 andproximal member 208 change their shape such that outer ends 214 and 216of members 206 and 208 are located outwardly even further from thedefined outer width 207 of main portion 204 than that of the location ofouter ends 214 and 216 of members 206 and 208 in the undeployed state.

As more clearly illustrated in FIG. 2C, although outer ends 214 and 216of members 206 and 208 are located outwardly from the defined width 207of main portion 204 by the same distance, it is possible that distalmember 206 has a greater distance between outer end 214 and inner end218 than a distance between outer end 216 and inner end 220 of proximalmember 208. In such an embodiment, a taper between outer end 214 andinner end 218 of distal member 206 is much more gradual compared to ataper between outer end 216 and inner end 220 of proximal member 208.Inserting distal member 206 that has a gradual taper compared toproximal member 208 having a more rapid taper into tympanic membrane 22(FIG. 1) will ensure that the device will not fall into cavity 24 (FIG.1), while still allowing it to eventually fall out through ear canal 20(FIG. 1).

FIG. 3 illustrates a perspective view of a ventilation device 300comprised at least partially of shape memory material in accordance withanother embodiment. Ventilation device 300 is also formed with a shapememory alloy or polymer similar to ventilation device 200, except,device 200 includes a plurality of distal members 306 and proximalmembers 308. While there is no difference in the intended functionalityof device 300 compared to device 200, the reduction in material ofhaving a plurality of members 306 and 308 instead of a single memberallows device 300 to regain the flanged or grommet shape more quicklywhile maintaining a low profile during insertion into the tympanicmembrane. Additionally, the plurality of members 306 and 308, can allowdeformations that could not be achieved with a single member or solidflange.

FIGS. 4A-4C illustrate a ventilation device 400 comprised at leastpartially of a shape memory material in accordance with yet anotherembodiment. In the perspective view of FIG. 4A, ventilation device 400is in an undeployed state. In the perspective view of FIG. 4B and in theside view of FIG. 4C, ventilation device 400 is in a deployed state.Like ventilation devices 200 and 300, ventilation device 400 includes ahollow body 402 made at least partially of a shape memory metal or shapememory polymer. Although ventilation device 400 is illustrated as havinga cylindrical, tube-like structure, other geometries are possible.

In one embodiment, ventilation device 400 is formed at least partiallywith a shape memory material in the deployed state as illustrated inFIGS. 4B and 4C. After formation, reversible deformation is applied toventilation device 400 to place it in the undeployed state asillustrated in FIG. 4A. In the undeployed state, ventilation device 400is able to be delivered to a membrane or other anatomical structure forinsertion. Upon addition of heat, such as heat applied from bodytemperature and removal of any mechanical constraint, ventilation device400 regains its deployed configuration as illustrated in FIGS. 4B and4C.

In FIGS. 4A-4C, body 402 of ventilation device 400 includes a mainportion 404, a distal member 406 and a proximal member 408. Distalmember 406 is coupled to a distal end 410 of main portion 404, whileproximal member 408 is coupled to proximal end 412 of main portion 404.While the entire body 402 can be formed of a shape memory material, itshould be realized that it is possible for main portion 404 or parts ofmain portion 404 to be formed of a different material than the shapememory materials of distal and proximal members 406 and 408.

Main portion 404 includes an outer wall 403 and an inner wall 405. Outerwall 403 and inner wall 405 extend from distal end 410 to proximal end412. As illustrated in FIG. 4C, outer wall 403 is defined by andincludes a continuous, fixed outer width or outer diameter 207 and innerwall 405 is defined by and includes a continuous, fixed inner width orinner diameter 209. In other words, main portion 404 remain unchangedbetween an undeployed state and a deployed state.

Both distal member 406 and proximal member 408 have outer ends 414 and416 and inner ends 418 and 420. Inner ends 418 and 420 are coupled todistal end 410 and proximal end 412, respectively, of main portion 404.In the undeployed state or reversible deformation state illustrated inFIG. 4A, outer ends 414 and 416 of members 406 and 408 extend fromdistal end 210 and proximal end 212 and are located within the definedouter width 407 of main portion 404. In the deployed state illustratedin FIGS. 4B and 4C, distal member 406 and proximal member 408 changetheir shape such that outer ends 414 and 416 of members 406 and 408 arelocated outwardly from the defined outer width 407 of main portion 404.As more clearly illustrated in FIG. 4C, it is possible that a distancefrom outer end 414 to inner end 418 of distal member 406 is smaller thana distance from outer end 416 to inner end 420 of proximal member 408.Inserting distal member 406 into tympanic membrane 22 will ensure thatthe device will not fall into cavity 24 (FIG. 1), while still allowingit to eventually fall out through ear canal 20 (FIG. 1).

FIGS. 5A-5C illustrate a ventilation device 500 at least partiallycomprised of a shape memory material in accordance with yet anotherembodiment. In the perspective view of FIG. 5A, ventilation device 500is in an undeployed state. In the perspective view of FIG. 5B and in theside view of FIG. 5C, ventilation device 500 is in a deployed state.Like ventilation devices 200, 300 and 400 ventilation device 500includes a hollow body 502 made of a shape memory metal or polymer.Although ventilation device 500 is illustrated as having a cylindrical,tube-like structure, other geometries are possible.

In one embodiment, ventilation device 500 is formed with a shape memorymaterial in the deployed state as illustrated in FIGS. 5B and 5C. Afterformation, reversible deformation is applied to ventilation device 500to place it in the undeployed state as illustrated in FIG. 5A. In theundeployed state, ventilation device 500 is able to be delivered totympanic membrane 22 or other anatomical structure for insertion. Uponaddition of heat, such as heat applied from body temperature and removalof any mechanical constraint, ventilation device 500 regains itsdeployed configuration as illustrated in FIGS. 5B and 5C.

In FIGS. 5A-5C, body 502 of ventilation device 500 includes a mainportion 504, a distal member 506 and a proximal member 508. Distalmember 506 is coupled to a distal end 510 of main portion 504, whileproximal member 508 is coupled to proximal end 512 of main portion 504.While the entire body 502 can be formed of a shape memory material, itshould be realized that it is possible for main portion 504 or parts ofmain portion 504 to be formed of a different material than the shapememory material of distal member 406.

Main portion 504 includes an outer wall 503 and an inner wall 505. Outerwall 503 and inner wall 505 extend from distal end 510 to proximal end512. As illustrated in FIG. 5C, outer wall 503 is defined by andincludes a continuous, fixed outer width or outer diameter 507 and innerwall 505 is defined by and includes a continuous, fixed inner width orinner diameter 509. In other words, main portion 504 remain unchangedbetween an undeployed state and a deployed state.

Both distal member 506 and proximal member 508 have outer ends 514 and516 and inner ends 518 and 520. Inner ends 518 and 520 are coupled todistal end 510 and proximal end 512, respectively, of main portion 504.In the undeployed state or reversible deformation state illustrated inFIG. 5A, outer end 514 of distal member 506 extends from distal end 510and located within the defined outer width 507 of main portion 504,while proximal member 508 extends from proximal end 512 and is locatedoutwardly from the defined outer width 507 of main portion 504. In otherwords, in the undeployed state, proximal member 508 is pre-formed orpre-deployed and is unaffected by heat. In one embodiment, proximalmember 508 can be made of a material other than a shape memory material.However, proximal member 508 can also be made of a shape memory materialthat has already been pre-deployed through a heating process such thatit is pre-formed. In the deployed state illustrated in FIGS. 5B and 5C,distal member 506 changes its shape such that outer end 514 of member506 is located outwardly from the defined outer width 507 of mainportion 504, while proximal member 508 does not change its shape. Asmore clearly illustrated in FIG. 5C, it is possible that a distance fromouter end 514 to inner end 518 of distal member 506 is smaller than adistance from outer end 516 to inner end 520 of proximal member 508.Inserting distal member 506 into tympanic membrane 22 (FIG. 1) willensure that the device will not fall into the cavity 24 (FIG. 1), whilestill allowing it to eventually fall out through ear canal 20 (FIG. 1).

FIGS. 6A-6D illustrate a ventilation device 600 at least partiallycomprising an elastically deformable material in accordance with oneembodiment. Example materials that demonstrate elastic deformation uponapplication of a constraint and are able to return to an undeformedstate upon removal of the constraint include a number of biocompatiblemetals such as Titanium, Silver, Tantalum, alloys of stainless steel,Cobalt Chromium, Alumina, Titanium etc; as well as polymers such aspolyolefins, polyurethanes, Silicone, PEEK, PMMA, fluoropolymers andothers known to those familiar in the art. In the perspective view ofFIG. 6A and the side view of FIG. 6B, ventilation device 600 is in adeployed state. In the perspective view of FIG. 6C and in the side viewof FIG. 6D, ventilation device 600 is in an undeployed state. Likeventilation devices 200, 300, 400 and 500 ventilation device 600includes a hollow body 602. At least a portion of body 602 is made of amaterial that can be elastically deformed into a position for deliveryto a membrane or other anatomical structure for insertion. Upon releaseof the elastic deformation, body 602 returns to its non-deformed stateand again forms its deployed configuration. Although ventilation device600 is illustrated as having a cylindrical, tube-like structure, othergeometries are possible.

In FIGS. 6A-6D, body 602 of ventilation device 600 includes a mainportion 604, a plurality of distal members 606 and a plurality ofproximal members 608. While the entire body 602 can be formed of anelastically deformable material, it should be realized that it ispossible for main portion 604 to be formed of a different material thanthe elastic deformation materials of distal and proximal members 606 and608. Distal members 606 are coupled to a distal end 610 of main portion604, while proximal members 608 are coupled to proximal end 612 of mainportion 604. Distal members 606 and proximal members 608 have outer ends614 and 616 and inner ends 618 and 620. Inner ends 618 and 620 arecoupled to distal end 610 and proximal end 612, respectively, of mainportion 604.

Main portion 604 includes an outer wall 603 and an inner wall 605. Outerwall 603 and inner wall 605 extend from distal end 610 to proximal end612. As illustrated in FIG. 6B, outer wall 603 is defined by andincludes a continuous, fixed outer width or outer diameter 607 and innerwall 605 is defined by and includes a continuous, fixed inner width orinner diameter 609. In other words, main portion 604 remains unchangedbetween an undeployed state and a deployed state.

In the undeployed state illustrated in FIGS. 6C and 6D where ventilationdevice is constrained into an elastically deformed position, outer ends614 and 616 of distal members 606 and proximal members 608 extend fromdistal end 610 and proximal end 612 and are located within the definedouter width 607 of main portion 604. In the deployed state illustratedin FIGS. 6A and 6B where the constraining component is removed, distalmembers 606 and proximal members 608 return to their non-deformed statesuch that outer ends 614 and 616 of members 606 and 608 are locatedoutwardly from the defined outer width 607 of main portion. Although notparticularly illustrated in FIGS. 6A-6D, it is possible that that adistance from outer ends 614 to inner ends 618 of distal members 606 aresmaller than a distance from outer ends 616 to inner ends 620 ofproximal members 608 to ensure that the device will not fall into cavity24 (FIG. 1), while still allowing it to eventually fall out through earcanal 20 (FIG. 1) from tympanic membrane 22 (FIG. 1).

FIGS. 7A-7D illustrate another embodiment of a ventilation device 700comprised at least partially of shape memory material. In theperspective view of FIG. 7A and the side view of FIG. 7B, ventilationdevice 700 is in an undeployed state and has a constraining component722. In the perspective view of FIG. 7C and in the side view of FIG. 7D,ventilation device 700 is in a deployed state with hollow body 702 movedaxially relative to constraining component 722 for formation ofventilation device 700. Like ventilation devices 200, 300, 400, 500 and600, ventilation device 700 includes a hollow body 702 located underconstraint component 722. In the embodiment illustrated in FIGS. 7A-7D,body 702 (shown in dashed lines in FIG. 7A) can be at least partiallymade of a shape memory material, such as a shape memory alloy orpolymer, which is reversibly deformable under constraining component722. Although ventilation device 700 is illustrated as having acylindrical, tube-like structure, other geometries are possible. Uponreleasing constraining component 722 and upon addition of heat, body 702can be returned to its undeformed state and again form its deployedconfiguration illustrated in FIGS. 7C and 7D.

In general, the constraint mechanisms shown and described are allexternal to the body in its deformed/undeployed state. It some cases itis possible to provide internal mechanisms to constrain the device fromreturning to its undeformed state. For example, in the case of theelastically deformed example, an internal sheath could be provided thatwould fit into undercuts formed into the internal flange on the device,holding the internal flange in the deformed state for deployment througha membrane. Retracting the internal crimping sheath from the undercutswould then allow the body to return to its undeformed state to form aninternal flange. This type of design could be advantageous in caseswhere a pre-formed external flange would prevent the use of an externalcrimping sheath.

In FIGS. 7A-7D, body 702 of ventilation device 700 includes a mainportion 704, a distal member 706 and a proximal member 708. Distalmember 706 is coupled to a distal end 710 of main portion 704, whileproximal member 708 is coupled to a proximal end 712 of main portion704. While the entire body 702 can be formed of a shape memory material,it should be realized that it is possible for main portion 704 or partsof main portion 704 to be formed of a different material than the shapememory material of distal member 706.

Main portion 704 includes an outer wall 703 and an inner wall 705. Outerwall 703 and inner wall 705 extend from distal end 710 to proximal end712. As illustrated in FIG. 5C, outer wall 703 is defined by andincludes a continuous, fixed outer width or outer diameter 707 an innerwall 705 is defined by and includes a continuous, fixed inner width orinner diameter 709. In other words, main portion 704 remains unchangedbetween an undeployed state and a deployed state.

Both distal member 706 and proximal member 708 have outer ends 714 and716 and inner ends 718 and 720. Inner ends 718 and 720 are coupled todistal end 710 and proximal end 712, respectively, of main portion 704.In an undeployed state or reversible deformation state illustrated inFIG. 7A, outer end 714 of distal member 706 extends from distal end 710and is located within the defined outer width 707 of main portion 704,while proximal member 708 extends from proximal end 712 and is locatedoutwardly from the defined outer width 707 of main portion 704. In otherwords, in the undeployed state, proximal member 708 is pre-formed orpre-deployed. It will be unaffected by heat. In one embodiment, proximalmember 708 can be made of a material other than a shape memory material.However, proximal member 708 can also be made of a shape memory materialthat has already been pre-deployed through a heating process such thatit is pre-formed. In the deployed state illustrated in FIGS. 7C and 7Dwhere body 702 moves axially relative to constraining component 722,distal member 706 is exposed to heat to return to a non-deformed shapesuch that outer end 714 of member 706 is located outwardly from thedefined outer width 707 of main portion 704, while proximal member 708does not change its shape.

As illustrated in FIGS. 7C and 7D, it is possible that a distance fromouter end 714 to inner end 618 of distal member 706 is smaller than adistance from outer end 716 to inner end 720 of proximal member 708 whenventilation device 700 is in a deployed state to ensure that the devicewill not fall into cavity 24 (FIG. 1), while still allowing it toeventually fall out through ear canal 20 (FIG. 1) from tympanic membrane22 (FIG. 1).

FIGS. 8A-8B illustrate yet another embodiment of a ventilation device800 comprising an elastically deformable material. In the perspectiveview of FIG. 8A, ventilation device 800 is in an undeployed state andhas a constraining component 822. In the perspective view of FIG. 8B,ventilation device 800 is in a deployed state with a hollow body 802moved relative to constraining component 822 for formation ofventilation device 800. Like ventilation devices 200, 300, 400, 500, 600and 700, ventilation device 800 includes hollow body 802 located underconstraining component 822. In the embodiment illustrated in FIGS.8A-8B, body 802 (shown in dashed lines in FIG. 8A) can be made of anelastically deformable material, which is deformed under constrainingcomponent 822. Upon sliding body 802 relative to constraining component822, a portion of body 802 can be returned to its non-deformed state andagain form its deployed configuration illustrated in FIG. 8B. Althoughventilation device 800 is illustrated as having a cylindrical, tube-likestructure, other geometries are possible.

In FIGS. 8A-8B, body 802 of ventilation device 800 includes a mainportion 804, a plurality of distal members 806 and a proximal member808. Distal members 806 are coupled to a distal end 810 of main portion804, while proximal member 808 is coupled to proximal end 812 of mainportion 804. While the entire body 802 can be formed of an elasticallydeformed material, it should be realized that it is possible for mainportion 804 or parts of main portion 804 to be formed of a differentmaterial than the elastically deformable material of distal member 806.

Main portion 804 includes an outer wall 803 and an inner wall 805. Outerwall 803 and inner wall 805 extend from distal end 810 to proximal end812. As illustrated in FIG. 8B, outer wall 803 is define by and includesa continuous, fixer outer width or outer diameter 807 and inner wall 805is defined by and includes a continuous, fixed inner width or innerdiameter 809. In other words, main portion 804 remains unchanged betweenan undeployed state and a deployed state.

Distal members 806 and proximal member 808 have outer ends 814 and 816and inner ends 818 and 820. Inner ends 818 and 820 are coupled to distalend 810 and proximal end 812, respectively, of main portion 804. In theundeployed state illustrated in FIG. 8A where ventilation device 800 isconstrained into an elastically deformed position, outer ends 814 ofdistal members 806 extend from distal end 810 are located within thedefined outer width 807 of main portion 804, while outer end 816 ofproximal member 808 extends from proximal end 812 and is locatedoutwardly from the defined outer width 807 of main portion 804. In otherwords, in the undeployed state, proximal member 808 is a pre-formed orpre-deployed. In the deployed state illustrated in FIGS. 8A and 8B wherethe device 802 is slid axially relative to constraining component 822,distal members 806 return to their non-deformed state such that outerends 814 of members 806 are located outwardly from the defined outerwidth 807 of main portion 804, while proximal member 808 does not changeits shape.

As illustrated in FIGS. 8A-8B, it is possible that a distance from outerend 814 to inner end 818 of distal members 806 is smaller than adistance from outer end 816 to inner end 820 of proximal member 808 whenventilation device 800 is in a deployed state to ensure that the devicewill not fall into cavity 24 (FIG. 1), while still allowing it toeventually fall out through ear canal 20 (FIG. 1) from tympanic membrane22 (FIG. 1).

FIGS. 9A-9B illustrate a ventilation device 900 comprised of a materialthat can be mechanically deformed in-situ in accordance with oneembodiment. In the perspective view of FIG. 9A, ventilation device 900is in an undeployed state. In the perspective view of FIG. 9B,ventilation device 900 is in a deployed state. Like ventilation devices200, 300, 400, 500, 600, 700, and 800, ventilation device 900 includes ahollow body 902 made of a mechanically deformable material, which can beone of a number of biocompatible materials such as Titanium, Silver,Tantalum, alloys of stainless steel, Cobalt Chromium, Alumina, Titaniumetc; as well as polymers such as polyolefins, polyurethanes, Silicone,PEEK, PMMA, fluoropolymers and others known to those familiar in theart. In one embodiment, ventilation device 900 is formed with a materialin the undeployed state as illustrated in FIG. 9A. After formation,device 900 is delivered to tympanic membrane 22 (FIG. 1) for insertion.To place ventilation device 900 in the deployed state as illustrated inFIG. 9B, body 902 is deformed in-situ. Although ventilation device 900is illustrated as having a cylindrical, tube-like structure, othergeometries are possible.

In FIGS. 9A-9B, body 902 of ventilation device 900 includes a mainportion 904, a distal end 910 and a proximal end 912. Body 902 includesa first set of slots 924 formed about a periphery of body 902 adjacentto distal end 910 and a second set of slots 926 formed about a peripheryof body 902 adjacent to proximal end 912. Slots 924 and 926 are formedthrough a thickness of body 902 between each of ends 910 and 912, but donot intersect ends 910 and 912. Between each slot 924 and 926 includesmaterial of body 902. In the undeployed state, material between eachslot 924 and 926 remains in alignment with body 902. In a deployed stateas illustrated in FIG. 9B, material between each slot 924 and 926 isdeformed to form a distal member 906 and a proximal member 908. Slots924 and 926 provide portions of body 902 that can more easily deform. InFIG. 9B, a part of each slot is folded to face against a remaining partof each slot. Distal member 906 and proximal member 908 have widths thatare greater than the width of main portion 904. Device 900 is insertedinto tympanic membrane 22 as illustrated in FIG. 9A and mechanicallydeformed into a shape as illustrated in FIG. 9B while device 900 isin-situ. The shape of FIG. 9B will ensure that the device will not fallinto cavity 24 (FIG. 1) and can eventually fall out through ear canal 20(FIG. 1). It should be obvious to those skilled in the art that a numberof different geometric shapes can be used to achieve the same results asslots shown in FIG. 9A.

It should be noted that FIG. 9B could be an ‘elastic deformation’embodiment as well as a ‘deformed in-situ’ embodiment. A part could beformed into the shape of FIG. 9B out of an appropriately elasticmaterial. It could subsequently be constrained to a deformed shapesimilar to that of FIG. 9A. Release of the constraining force wouldresult in the device elastically returning to its original shape (FIG.9B).

FIGS. 10A-10B illustrate other embodiments of ventilation devices 1000Aand 1000B comprising an elastically deformable material. In theperspective view of FIG. 10A, ventilation device 1000A is in deployed orundeployed state and in the perspective view of FIG. 10B, ventilationdevice 1000B is in deployed states. Ventilation device 1000A include abodies 1002A having a first axial edge 1028A and second axial edge1030A. Body 1002A is made of elastic deformable material such that itcan be rolled from first axial edge 1028A to second axial edge 1030A toform a hollow tubular shape.

In an undeployed state, the rolled hollow shape of body 1002A iscompressed (or more tightly rolled) such that its diameter is smallerthan the diameter in its deployed state. In its deployed state, body1002A expands (or unrolls). The rolling and unrolling of body 1002Aprovides device 1000A the requisite deformation for maintaining anopening in a membrane in a body without the need for proximal or distalmembers. In the undeployed state, ventilation device 1000A is able to bedelivered to a membrane in a body for insertion. Upon removal of amechanical constraint, ventilation device 1000A regains its deployedconfiguration.

In the perspective view, FIG. 10B illustrates ventilation device 1000Bin a deployed state having a pair of distal members 1006 attached to adistal end 1010. Like the rolled embodiment illustrated in FIG. 10A,distal members 1006 are compressed (more tightly rolled) such they arelocated close to each other. In the deployed state illustrated in FIG.10B, members 1006 expand or unrolls. The rolling or unrolling body 1002Aprovides device 1000B the requisite deformation for maintaining anopening in a membrane in a body. In the undeployed state, ventilationdevice 1000B is able to be delivered to a membrane in a body forinsertion. Upon removal of a mechanical constraint, ventilation device1000B regains its deployed configuration.

FIGS. 11A-11D illustrate a ventilation device 1100 comprised at leastpartially of a shape memory material, such as a shape memory metal orpolymer, in accordance with yet another embodiment. It should berealized however, ventilation device 1100 can be made of other types ofmaterials or combinations of other types of materials and shape memorymaterials. In the perspective view of FIG. 11A, ventilation device 1100is in a first undeployed state. In the perspective view of FIG. 11B andin the side view of FIG. 11C, ventilation device 1100 is in a deployedstate. In the perspective view of FIG. 11D, ventilation device 1100 isin a second undeployed state. Like other above-described ventilationdevices, ventilation device 1100 includes a hollow body 1102. Althoughventilation device 1100 is illustrated as having a cylindrical,tube-like structure, other geometries are possible.

In one embodiment, at least a portion of ventilation device 1100 isformed with a shape memory material in the deployed state as illustratedin FIGS. 11B and 11C. After formation, reversible deformation is appliedto ventilation device 1100 to place it in the first undeployed state asillustrated in FIG. 11A or in the second undeployed state as illustratedin FIG. 11D. In either the first or second undeployed states,ventilation device 1100 is able to be delivered to a membrane in a bodyfor maintaining an opening in the membrane. Upon addition of heat, suchas heat applied from body temperature and removal of any mechanicalconstraint, ventilation device 1100 regains its deployed configurationas illustrated in FIGS. 11B and 11C.

In FIGS. 11A-11D, hollow body 1102 of ventilation device 1100 includes amain portion 1104, a pair of distal members 1106 and a pair of proximalmembers 1108. However, it should be realized that other quantities arepossible. Distal members 1106 are coupled to a distal end 1110 of mainportion 1104, while proximal members 1108 are coupled to proximal end1112 of main portion 1104. While the entire body 1102 can be formed of ashape memory material, it should be realized that it is possible formain portion 1104 or parts of main portion 1104 to be formed a differentmaterial than the shape memory material

Main portion 1104 includes an outer wall 1103 and an inner wall 1105.Outer wall 1103 and inner wall 1105 extend from distal end 1110 toproximal end 1112. As illustrated in FIG. 11C, outer wall 1103 isdefined by an includes a continuous, fixed outer width or outer diameter1107 and inner wall 1105 is defined by and includes a continuous, fixedinner width or inner diameter 1109. In other words, main portion 1104remains unchanged between an undeployed state and a deployed state.

The thickness between outer wall 1103 and inner wall 1105 of mainportion 1104 and the wall thickness of distal and proximal members 1106and 1108 can be the same or different. A thin wall between outer wall1103 and inner wall 1105 of main portion 1104 is desirable because itmaximizes the internal diameter (in the case of a tube-like geometry),while minimizing the external diameter (in the case of a tube-likegeometry). A large internal diameter is beneficial because it provides agreater cross-sectional area for venting and prevents plugging. Thethickness between outer wall 1103 and inner wall 1105 should be greatenough to provide the structural properties necessary to prevent thedevice from being crushed or squeezed closed. However, the thicknessbetween outer wall 1103 and inner wall 1105 should be thin enough toallow the necessary deformation between the deployed and undeployedstates to remain in the elastic or super-elastic ranges and to preventcracking or failure at the deformation points. For example, wallthicknesses of the proximal and distal members 1106 and 1108 as well asthe thickness between outer wall 1103 and inner wall 1105 of mainportion 1104 can be approximately between 0.0015 to 0.020 inches. Intympanic membrane applications, wall thicknesses of approximatelybetween 0.0015 to 0.008 inches are sufficient to prevent crushing whilestill minimizing the outer diameter of the vent and insertion device andproviding ease of placement and visualization in confined spaces. Insinus applications, wall thicknesses of approximately greater than 0.005inches are necessary to prevent crushing. It should be noted, the wallthicknesses described require that a rigid or semi-rigid material, suchas Nitinol, be used. Wall thicknesses for vents made of silicone rubber,for example, would need to be thicker to maintain an open vent, whilerigid plastic may require thicker walls for strength.

Distal members 1106 and proximal members 1108 have outer ends 1114 and1116 and inner ends 1118 and 1120. Inner ends 1118 and 1120 are coupledto distal end 1110 and proximal end 1112, respectively, of main portion1104. In the first undeployed state or first reversible deformationstate illustrated in FIG. 11A, outer ends 1114 and 1116 of distalmembers 1106 and proximal members 1108 extend from distal end 1110proximal end 1112 and are located within the defined outer width 1107 ofmain portion. In the deployed state illustrated in FIGS. 11B and 11C,distal members 1106 and proximal members 1108 return to theirnon-deformed state such that their outer ends 1114 and 1116 extend fromdistal end 1110 and proximal end 1112 and are located outwardly from thedefined outer width 1107 of main portion 1104.

In one embodiment, members 1106 and 1108 can be made of a shape memorymaterial, while main portion 1104 can be made of other types ofmaterials. As illustrated in FIGS. 11A-11D, members 1106 extend fromdistal end 1110 of main portion 1104. Each member 1106 is coupled to andpositioned about main portion 1104 180 degrees from each other. In otherwords, each member 1106 is positioned opposite from each other andfacing each other on distal end 1110. Members 1108 extend from proximalend 1112 of main portion 1104. Each member 1108 is coupled to andpositioned about main portion 1104 180 degrees from each other. In otherwords, each member 1108 is positioned opposite from each other andfacing each other on proximal end 1112. It should be realized thatmembers 1106 and 1108 can be located at different positions from eachother than illustrated. For example, a first distal member can belocated about distal end 1110 between 0 and 180 degrees from the seconddistal member. Likewise, a first proximal member can be located aboutproximal end 1112 between 0 and 180 degrees from the second proximalmember.

Each member 1108 is located about proximal end 1112 similar to eachmember 1106 located about distal end 1110. However, each member 1108 islocated about proximal end 1112 approximately 90 degrees from thelocation of each member 1106 around distal end 1110. These orientationsof members 1106 and 1106 are clearly illustrated in the side view ofFIG. 11C. It should be realized, though, that the embodimentsillustrated in FIGS. 11A-11D are exemplary and various otherconfigurations are possible. For example, each member 1108 can belocated about proximal end 1112 between 0 and 90 degrees from thelocation of each member 1106.

In the first undeployed state or first reversible deformation stateillustrated in FIG. 11A, the outer ends 1116 of members 1106 and 1108extend from distal end 1110 and proximal end 1112 and are located withinthe outer width 1107 of main portion 1104. In the second undeployedstate or second reversible deformation state illustrated in FIG. 11D,the outer ends 1114 of distal members 1106 extend from distal end 1110and are located within in the outer width 1107 of main portion 1104.However, the outer end 1116 of one of the proximal members 1108 extendsfrom proximal end 1112 and is located within the outer width 1107 ofmain portion 1104, but the outer end 1116 of the other of the proximalmembers 1108 extends from proximal end 1112 and is located outwardlyfrom the defined outer width 1107 of main portion 1104. In other words,in the second undeployed state, one of members 1108 is pre-formed orpre-deployed and is unaffected by heat. In one embodiment, thepre-deployed member 1108 can be made of a material other than a shapememory material. However, both members 1108 can also be made of a shapememory material that has already been pre-deployed through a heatingprocess such that it is pre-formed. In the deployed state illustrated inFIGS. 11B and 11C, Both members 1106 and one of members 1108 changestheir shape while the other of member 1108 that was pre-deployed doesnot change its shape.

A ventilation device can be coated with various materials to provideadded benefit. For example, antimicrobial coatings could be applied tolimit formation of biofilm, prevent premature blocking, limit infection,etc. Silver coating can also be applied to any of the materials used tomake the ventilation device by pulsed deposition in a plasma vacuumchamber. Biofilm formation on the ventilation device may be delayed bythe use of a biologic coating such as elastin, or collagen, laminin,etc. In another example, the device could be drug eluting. Drugs elutedfrom the surface of the device can provide anesthetic effects, limit thegrowth of cells on or near the device, promote the growth of cells on ornear the device, or provide a local drug treatment. In fact, aventilation device could itself deliver cells to focal regions.Ventilation devices can be treated to allow visualization with variousmedical imaging systems, such as radio opaque markers. In addition, aventilation device can be made of biodegradable material (such aspolymeric materials including co-polymers of PLA & PGA, Tyrosinepolycarbonate, or metal alloys such as Iron and Magnesium).

FIGS. 11E and 11F illustrate additional alternative embodiments ofventilation device 1100 in deployed positions. It would be possible,using the same shape memory materials described in the aforementionedembodiments, to have at least one distal member or flange 1106, at leastone proximal member or flange 1108, or both, that deform or extendinwardly when deployed, while the other of the members deform or extendoutwardly when deployed or remain same between the undeployed anddeployed states. In other words, at least one of the outer end 1114 ofdistal member 1106 and/or at least one of the outer end 1116 of proximalmember 1108 are located inwardly from the defined width of main portion1104 when deployed. Flanges and/or members that deform inwardly could becombined in any fashion with other distal or proximal members or flangesincluded in device 1100 that are located outwardly from the definedwidth of main portion 1104. One could have the outer end of at least onemember located inwardly from the defined width of main portion 1104 onone, both or neither end in a deployed state, along with the outer endof at least one member located outwardly from the defined width of mainportion 1104 on one, both, or neither end in a deployed state. It wouldalso be possible, with the inward deployment state, to create a pluginstead of a vent, for example, to close or seal off a pre-existing holein an anatomical structure.

For example, in FIG. 11E, ventilation device 1100 includes outer ends1114 of distal members 1106 as being located inwardly from the definedwidth of main portion 1104 in a deployed state, while outer ends 1116 ofproximal members 1108 are located outwardly from the defined width ofmain portion 1104 in the deployed state. The inwardly deployed ends 1114could create a plug. As noted earlier, but not illustrated, outer ends1114 of distal members 1106 could be located outwardly from the definedwidth of main portion 1104 in a deployed state, while outer ends 1116 ofproximal member 1108 could be located inwardly from the defined width ofmain portion 1104 in the deployed state.

For example, in FIG. 11F, ventilation device 1100 includes an outer end1114 of at least one of the distal members 1106 as being locatedinwardly from the defined width of main portion 1104 in a deployed stateand an outer end 1114 of the other of the distal members as beinglocated outwardly from the defined width of main portion 1104 in thedeployed state, while the outer end 1116 of at least one or more of theproximal members 1108 is located outwardly from the defined width ofmain portion 1104 in the deployed state. As noted earlier, but notillustrated, an outer end 1116 of at least one of the proximal members1108 could be located inwardly from the defined width of main portion1104 in a deployed state and an outer end 1114 of the other of theproximal members as being located outwardly from the defined width ofmain portion 1104 in the deployed state, while the outer end 1114 of atleast one or more of the distal members 1106 is located outwardly fromthe defined width of main portion 1104 in the deployed state. It shouldbe realized that any variation of each distal or proximal member ondevice 1100 could be located outwardly from the defined width of mainportion 1104, located inwardly from the defined width of main portion1104 or in alignment with the define width of main portion 1104 in adeployed state.

FIG. 12A illustrates a perspective view of an insertion system 1240 inaccordance with one embodiment. Insertion system 1240 is configured foruse in inserting ventilation device 1100 (FIGS. 11A-11D) into ananatomical structure of a body. Insertion system 1240 includes aninsertion end or distal end 1241 including a rod member 1242 and asheath member 1244, which has a cutting edge 1246. Sheath member 1244surrounds a portion of rod member 1242 at insertion end 1241.

Insertion system 1240 includes an actuation end 1243 including anactuator 1248, a handle 1249 and a flexible actuation member 1250coupling the actuator to the sheath member 1244. Flexible actuationmember 1250 is made of a flexible material, such as plastic or thinmetal wire. Rod member 1242 protrudes from handle 1249 and bends alongan angle. For example, rod member 1242 can be bent from handle 1249 atan angle of approximately 60 degrees. However, it should be realizedthat other angles are possible. Flexible actuation member 1250 runs froma portion of actuator 1248 housed within handle 1249 until it reaches anaperture in rod member 1242 where flexible actuation member 1250 movesto the outside of the device and is coupled to sheath member 1244.

Insertion system 1240 also includes a suction member 1251 located withinhandle 1249 and coupled to a fitting 1253 for attachment to a suctionline. Handle also includes apertures 1255. When inserting insertion endinto an anatomical cavity and after cutting edge 1246 forms an incisionin an anatomical structure of a body, the clinician may need to removefluid. To remove the fluid, the clinician can cover apertures 1255 todirect the suction force provided by suction member 1251 to theinsertion end 1249. Thereby, fluid can be drained away from theanatomical structure through the sheath member 1244 and the rod member1242 and outwards through the suction member 1251.

In general, a ventilation device, such as ventilation device 1100 isloaded onto insertion system 1240 at the insertion end 1241. With sheathmember 1244 surrounding the distal end of rod member 1244, the distalends of rod member 1244 and sheath member 1244 are inserted into an earcanal or other anatomical cavity. The cutting edge 1246 of sheath member1244 makes an incision in an anatomical structure, such as a tympanicmembrane. After the membrane is cut and the sheath member 1244 islocated far enough through the membrane, actuator 1248 is actuated topull sheath member 1244 back, while rod member 1242 allows ventilationdevice 1100 to remain in place. The delivery and insertion of device1100 will be described in detail below.

FIG. 12A illustrates one type of actuator 1248. Other variations ofactuators are possible as long as the actuator is able to keep a distalend of rod member 1242 rigidly against a ventilation device to hold theventilation device in place during sheath member 1244 insertion andsheath member removal. For example, actuator 1248 includes a spring, anarm and flexible actuation member 1250 coupled to the spring, the armand the sheath member 1244. To remove sheath member 1244 without movingrod member 1242 or the ventilation device, the arm can be actuated topull on the flexible actuation member 1250.

FIG. 12B illustrates an enlarged perspective view of the sheath member1244 illustrated in FIG. 12A. Sheath member 1244 is a hollow member madeof a metallic material having a distal end 1252 and a proximal end 1253.Distal end 1252 includes cutting edge 1246 that forms part of a tapereddistal end 1252. Distal end 1252 tapers from one side of the hollowmember to the other side of the hollow member such that the length ofsheath member 1244 is shorter on one side than the other side. The sidewith the longer length terminates at cutting edge 1246. Although notspecifically illustrated in FIGS. 12A-12D, distal end 1252 of sheathmember can include other topographies than that which is illustrated.For example, the tapered proximal end can also include certain bevels orbeveled edges to make cutting edge 1246 more conducive for piercing amembrane to mitigate resistive forces from the membrane. Sheath member1244 also includes a slot 1254. Slot 1254 includes a distal end 1256 anda proximal end 1257. Distal end 1256 of slot 1254 is in communicationwith tapered end or distal end 1252 of sheath member 1244.

FIG. 12C illustrates an enlarged perspective view of the insertion end1241 of insertion system 1240 and FIG. 12D illustrates a side sectionalview of insertion end 1241 of insertion system 1240. FIGS. 12C and 12Dillustrate a portion of rod member 1242, the sheath member 1244, aportion of flexible actuation member 1250 and the ventilation device1100 loaded onto the device. Rod member 1242 includes an aperture 1258where flexible actuation member 1250 moves from a position within system1240 and within rod member 1242 to a position external to system 1240 orrod member 1242 such that it can couple to sheath member 1244 at acoupling point 1260. Flexible actuation member 1250 can couple to sheathmember 1244 by solder, for example. However, other forms of attachmentare possible.

A distal end 1262 of rod member 1242 and its external surface arepositioned within and adjacent an internal surface of sheath member1244. In other words, sheath member 1244 surrounds the distal end 1262of rod member 1242. Ventilation device 1100 is loaded within sheathmember 1244 such that the sheath member encloses device 1100 exceptwhere slot 1254 is located in the sheath member. Ventilation device 1100is also loaded such that distal end 1262 of rod member 1242 is adjacentproximal end 1112 of device 1100.

As illustrated in FIGS. 12C and 12D, ventilation device 1100 is in thesecond undeployed state or second reversible deformation stateillustrated in FIG. 11D when loaded onto insertion system 1240. Morespecifically, the outer ends 1114 of distal members 1106 extend fromdistal end 1110 within the defined outer width 1107 (FIG. 11C) of mainportion 1104 (FIGS. 11A-11D). However, the outer end 1116 of one of theproximal members 1108 extends from proximal end 1112 within the definedouter width 1107 of main portion 1104, but the outer end 1116 of theother of the proximal members 1108 extends from proximal end 1112outwardly from the defined outer width 1107 of main portion 1104. Thismember 1108 extends from away from rod member 1242 and through slot 1254of sheath member 1244. Such a pre-deployed member 1108 acts as a visualindicator to a clinician. As will be discussed more thoroughly in FIGS.13A-13D, the clinician will insert sheath member 1244 through ananatomical structure only as far as the location of the pre-deployedmember 1108.

FIGS. 13A-13D illustrate a process of inserting and deploying theventilation device 1100 of FIGS. 11A-11D into an anatomical structure1260 using the insertion system 1240 illustrated in FIGS. 12A-12D underone embodiment. In FIGS. 13A-13C, ventilation device 1100 is shown inthe second undeployed state or second reversible deformation stateillustrated in FIG. 11D. In FIG. 13D, ventilation device 1100 is shownin the deployed state illustrated in FIGS. 11B and 11C.

In FIG. 13A, insertion system 1240 has been inserted into an anatomicalcavity of a body in preparation for insertion into anatomical structure1260. As illustrated, sheath member 1244 surrounds distal end 1262 ofrod member 1242 and ventilation device 1100. In FIG. 13B, cutting edge1246 of sheath member 1244 slices through anatomical structure 1260 suchthat a distal end of the sheath member is inserted through structure1260 until a clinician can visually see the pre-deployed member 1108 ofventilation device 1100 is next to structure 1260.

In FIG. 13C, the clinician actuates insertion system 1240 such thatsheath member 1244 is pulled out of anatomical structure 1260 along thelength of rod member 1242, while the rod member remains fixed in placeto make sure ventilation device 1100 remains inserted in anatomicalstructure 1260. Upon ventilation device 1100 being heated by the body,the ventilation device deploys into a deployed state as illustrated inFIG. 13D. Then, the clinician pulls insertion system 1240 includingsheath member 1244 and rod member 1242 back through the anatomicalcavity and away from the ventilation device 1100 now positioned anddeployed in anatomical structure 1260.

FIG. 14 illustrates a side view of an insertion end of an insertiondevice 1440 in accordance with another embodiment. Insertion system 1440is configured for use with the ventilation devices 200, 300, 400 and 600illustrated in FIGS. 2, 3, 4 and 6. In FIG. 14, insertion system 1440includes a cutting member 1445, a rod member 1442 and a sheath member1444. Cutting member 1445 includes a cutting edge 1446 for use inpiercing a membrane, such as a tympanic membrane. However, cuttingmember 1445 can also be used to both aspirate fluids out of the earand/or to deliver local analgesics, antibiotics, etc. Cutting member1445, rod member 1442 and sheath member 1444 are all cylindricallyshaped bodies that are nested within each other. In particular, rodmember 1442 surrounds cutting member 1445 and sheath member 1444surrounds both rod member 1442 and cutting member 1445. A ventilationdevice 1400 is mounted around cutting member 1445. Sheath member 1444holds device 1400 in a deformed state, as applicable for an elasticallydeformable device (i.e., device 500) or hold device 1400 in a reversiblydeformed state, as applicable for a shape memory material device, suchas devices 100, 200 and 300. Rod member 1442 holds device 1400 inposition as sheath member 1444 is retracted. Sheath member 1444 isretracted once device 1400 is successfully positioned. In FIG. 14,ventilation device 1400 is shown with sheath member 1444 partlyretracted. However, device 1400 normally would be completely insidesheath member 1444 until it is in position for deployment.

As also illustrated, sheath member 1444 includes positioning markerbands 1401 and 1403. Positioning marker bands 1401 and 1403 are for usein allowing a clinician to visualize when device 1400 is correctlyinserted into a membrane or other anatomical structure. In particular,one marker band 1401 is placed on one side of a membrane or anatomicalstructure and the other marker band 1402 is placed on the other side ofthe membrane to show correct placement.

Marker bands 1401 and 1403 are an example of a visual indicator to aidthe user in determining when the insertion device is correctly placedfor deployment. A clear or translucent sheath member can also serve thissame function to allow the user to see the device and to position itcorrectly. A combination of marker bands and a clear crimping sheath canalso be employed. Marker bands can be on the device, but visible throughthe crimping sheath. It is necessary to ensure that the insertion devicedoes not block visual access to the application/deployment site. Forexample, when a ventilation device is to be placed through a membrane ina constrained space, such as in ear-tube applications, an appropriate‘bend’ in the delivery system (for example, a 30, 45, 60, or 90 degreebend) that allows the user to actuate the device deployment mechanismwithout blocking their site lines could be incorporated with any of theembodiments discussed. A flexible delivery system could also beemployed. An example 60 degree bend is illustrated in FIG. 12A ininsertion system 1240. Such a system would allow the user to flex thedelivery system in any direction favorable to maintaining sight lines.

FIG. 15 illustrates a side view of an insertion end of an insertionsystem 1540 in accordance with another embodiment. Insertion device 1540is similar to system 1440 except instead of including positioningmarking bands, sheath member 1544 includes a stop 1543 to allow aclinician to place the device correctly. Stop 1543 will prevent aclinician from inserting system 1540 any further into a middle ear suchthat device 1500 will have a correct placement for deployment.

Physical stops, as illustrated in FIG. 15 can be included on thecrimping sheath as one example of a mechanical positioning aid. However,stops can also be present that are not located on the sheath member. Forexample, a completely redundant component could incorporate a stop, sothat the stop remains stationary while the sheath member is retracted toensure the correct placement is maintained during deployment. In theembodiment illustrated in FIGS. 12A-12D, a pre-deployed portion of theventilation device can be used as a positioning aid by placing it flushagainst (or at some offset from) the outside of the membrane.

FIG. 16A illustrates a side view of a portion of a cutting member 1645and FIG. 16B illustrates a side view of a portion of an insertion system1640 including cutting member 1645 in accordance with an embodiment inwhich ventilation device 1600 is deformed in-situ. As illustrated inFIGS. 16A and 16B, cutting member 1645 has a device (i.e., bumper orstop) 1680 that allows a distal end 1610 of ventilation device 1600 tobe deformed to a flange like structure. In another embodiment, device1680 can be either expanded or retracted similar to a balloon to allowdeformation of the ends of the tubular structure into a flange orgrommet like structure. Device 1680 can be present either at both endsor just at distal end 1610 so that once a member or members are deployedor created in-situ, the device will not fall into a cavity (such as themiddle ear), while still allowing it to eventually fall out through theear canal from the tympanic membrane.

FIG. 17 illustrates a side view of another embodiment of an insertionsystem 1740 which can be used to create an in-situ ventilation device orgrommet 1700. A cutting member 1745 includes a device 1780, such as astop or bumper that is used to deform the ventilation device 1700.Device 1780 is expandable and retractable by applying relative motionvia a sheath member 1744.

FIGS. 18A-18C and FIGS. 19A-19C illustrates embodiments of insertionsystems 1840 and 1940 for inserting shape memory ventilation devices. InFIGS. 18A-18C, a sheath member 1844 is used to constrain a ventilationdevice 1800. When the sheath member 1844 is pulled back, it allows theend or ends of the ventilation device 1800 to deploy into a flangeshape. Sheath member 1844 and cutting member 1845 are then pulled out ofthe auditory canal leaving the ventilation device 1800 in the tympanicmembrane. In FIGS. 19A-19C, a sheath member 1944 is used to keep theundeployed ventilation device 1900 constrained into a low profile shape.The difference with the version illustrated in FIGS. 18A-18C is that thesheath member 1944 deploys by rolling back on itself. The versionillustrated in FIGS. 18A-18C allows a lower profile while the latter onemay allows a smoother delivery and deployment of the ventilation device1900.

FIG. 20 illustrates a perspective view of an insertion system 2040having a sheath member 2044 located proximal to the device 2000. Thisarrangement allows for the proximal member of the device 2000 to bepreformed or pre-deployed, acting as a positioning aid and ensuring thatthe device cannot be deployed too deeply. Sheath member 2044 is locateddistal to device 2000 and is used to constrain the distal member. FIG.20 illustrates the device ready for deployment.

All the embodiments of the insertion systems described above may requirea lubricious coating on the ventilation device and/or the sheath memberto allow the device to be inserted or deployed efficiently. In oneembodiment, any of the ventilation devices mentioned above may bespray-coated or dip-coated in a mixture of latex or a polymer such assilicone and an antimicrobial agent such as nitrofurazone.Alternatively, the device may be coated in silver Hydrogel to achievethe same effect. Silver coating may be applied via deposition in avacuum chamber.

Although many of the embodiments described have been illustrated using ashape memory material that is activated by a temperature change toreturn to its heat set shape, it should be understood that thesuper-elastic properties of a shape memory material could also be used.For example, a shape-memory ventilation tube that would return to itsheat set shape at a temperature lower than body temperature could berestrained within a sheath and the super-elastic properties would allowit to return to its undeformed state upon deployment.

Although the subject matter has been described in language specific tostructural features and/or methodological acts, it is to be understoodthat the subject matter defined in the appended claims is notnecessarily limited to the specific features or acts described above.Rather, the specific features and acts described above are disclosed asexample forms of implementing the claim.

1. A ventilation device comprising: a hollow body having a main portion,at least one distal member coupled to a distal end of the main portionand at least one proximal member coupled to a proximal end of the mainportion, wherein at least the distal member comprises a shape memorymaterial, the hollow body comprising: a deployed state for maintainingan opening in an anatomical structure, wherein the shape memory materialforms at least the distal member into a deployed position; an undeployedstate for inserting the hollow body into an opening in an anatomicalstructure, wherein the shape memory material is reversibly deformed fromthe deployed state into the undeployed state such that at least thedistal member changes in shape to an undeployed position while the mainportion of the hollow body remains unchanged.
 2. The ventilation deviceof claim 1, wherein the main portion comprises inner and outer wallsextending from the distal end to the proximal end of the main portion,the outer wall defined by a continuous, fixed outer width and the innerwall defined by a continuous, fixed inner width.
 3. The ventilationdevice of claim 2, wherein each distal member extends from the distalend of the main portion to an outer end that is located within thedefined outer width of the outer wall of the main portion in theundeployed state and each outer end of each distal member that extendsfrom the distal end of the main portion is located outwardly from thedefined outer width of the main portion in a deployed state.
 4. Theventilation device of claim 2, wherein each proximal member extends fromthe proximal end of the main portion to an outer end that is locatedwithin the defined outer width of the main portion in the undeployedstate and each outer end of each proximal member that extends from theproximal end of the main portion is located outwardly from the definedouter width of the main portion in a deployed state.
 5. The ventilationdevice of claim 1, wherein the at least one distal member coupled andlocated about the distal end is between approximately 90 to 180 degreesfrom the at least one proximal member coupled and located about theproximal end.
 6. The ventilation device of claim 2, wherein coupled tothe proximal end of the main portion comprises first and second proximalmembers, the outer end of the first proximal member is located outwardlyfrom the defined outer width of the main portion in both an undeployedstate and in the deployed state, the outer end of the second proximalmember is located within the defined outer width of the main portion inan undeployed state and located outwardly from the defined outer widthof the main portion in the deployed state.
 7. The ventilation device ofclaim 2, wherein coupled to the distal end of the main portion comprisesfirst and second distal members, the outer ends of the first and seconddistal members are located within the defined outer width of the mainportion in an undeployed state and are located outwardly from thedefined outer width of the main portion in the deployed state.
 8. Theventilation device of claim 1, wherein coupled to the proximal end ofthe main portion comprises first and second proximal members and coupledto the distal end of the main portion comprises first and second distalmembers, wherein first and second proximal members are coupled andlocated about the proximal end of the main portion substantially 180degrees from each other and wherein first and second distal members arecoupled and located about the distal end of the main portion 180 degreesfrom each other.
 9. The ventilation device of claim 7, wherein the firstand second proximal members oppose each other about the proximal end ofthe main portion substantially between 0 and 90 degrees from the firstand second distal members that oppose each other about the distal end ofthe main portion.
 10. A ventilation device comprising: a hollow bodycomprising: a main portion having an inner wall, an outer wall, a distalend and a proximal end, wherein the outer wall of the main portion isdefined by a continuous, fixed outer width; at least one distal membercoupled to and extending from the distal end of the main portion, eachdistal member having an outer end located within the defined outer widthof the main portion in an undeployed state and each distal member havingthe outer end located outwardly from the defined outer width of the mainportion in a deployed state; and at least one proximal member coupled toand extending from the proximal end of the main portion, the at leastone proximal member having an outer end located outwardly from thedefined outer width of the main portion in both the undeployed state andthe deployed state.
 11. The ventilation device of claim 10, whereincoupled to the proximal end of the main portion comprises first andsecond proximal members, the outer end of the first proximal memberlocated outwardly from the defined outer width of the main portion inboth the undeployed state and the deployed state, the outer end of thesecond proximal member located within the defined outer width of themain portion in the undeployed state and located outwardly from thedefined outer width of the main portion in the deployed state.
 12. Theventilation device of claim 10, wherein coupled to the distal end of themain portion comprises first and a second distal members, the outer endsof the first distal member and the second distal member located withinthe defined outer width of the main portion in the undeployed state andlocated outwardly from the defined outer width of the main portion inthe deployed state.
 13. The ventilation device of claim 10, whereincoupled to the proximal end of the main portion comprises first andsecond proximal members and coupled to the distal end of the mainportion comprises first and second distal members, wherein first andsecond proximal members oppose each other about the proximal end of themain portion and wherein first and second distal members oppose eachother about the distal end of the main portion.
 14. The ventilationdevice of claim 13, wherein the first and second proximal members opposeeach other about the proximal end of the main portion at a firstlocation substantially 90 degrees from a second location of the firstand second distal members that oppose each other about the distal end ofthe main portion.
 15. The ventilation device of claim 10, wherein the atleast one distal member coupled and located about the distal end isbetween approximately 90 to 180 degrees from the at least one proximalmember coupled and located about the proximal end.
 16. The ventilationdevice of claim 10, wherein the at least one distal member comprises ashape memory material.
 17. An insertion system comprising: a hollowsheath member including a distal end having a cutting edge and aproximal end, the hollow sheath member configured to at least partiallysurround a ventilation device having a distal end and a proximal end formaintaining an opening in an anatomical structure; a rod memberincluding a distal end, wherein the distal end of the rod member islocated within the sheath member and configured to be adjacent theproximal end of the ventilation device; and an actuator configured tohold the distal end of the rod member adjacent to the proximal end ofthe ventilation device while simultaneously retracting the sheath memberfrom around the ventilation device to slide it over the rod member. 18.The insertion system of claim 17, wherein the distal end of the sheathmember is tapered such that a first side of the sheath member has alength that is greater than a second side of the sheath member, whereinthe cutting edge is located where the first side of the sheath memberterminates at the distal end.
 19. The insertion system of claim 18,wherein the second side of the sheath member comprises a slot, whereinthe distal end of the slot is in communication with the distal end ofthe sheath member.
 20. The insertion system of claim 19, wherein theslot is configured to allow a proximal member coupled to the proximalend of the ventilation device to protrude through and outwardly from thesheath member
 21. The insertion system of claim 17, further comprising aflexible actuation member coupling the actuator to the sheath member,the flexible actuation member configured to retract the sheath memberfrom the ventilation device while the rod member is kept adjacent theproximal end of the ventilation device.
 22. The insertion system ofclaim 17, further comprising a suction member configured to evacuatefluid through the opening in the anatomical structure.
 23. A method ofmaintaining an opening in an anatomical structure of the body, themethod comprising: obtaining an insertion device including a rod memberhaving a distal end and a sheath member having a cutting edge andsurrounding a portion of the rod member; inserting a ventilation deviceinto the sheath member such that the distal end of the rod member isadjacent a proximal end of the ventilation device; inserting a distalend of the insertion device into a cavity of a body to make an incisionin the anatomical structure of the body, the device is inserted suchthat a portion of the ventilation device is located in the incision;retracting the sheath member while the distal end of the rod memberremains adjacent to the proximal end of the ventilation device that ispartially through the incision; and removing the rod member and thesheath member from the cavity to thereby leave the ventilation device inthe incision.
 24. The method of claim 22, wherein retracting the sheathmember comprises retracting the sheath member using the flexibleactuation member that couples an actuation device to the sheath member.25. The method of claim 22, wherein inserting the distal end of theinsertion device such that a portion of the ventilation device islocated in the incision comprises inserting the insertion device until apre-deployed proximal member coupled to a proximal end of theventilation device is located adjacent the anatomical structure.